PhotoCyX · Seeing in the New Light: Photoreceptor Expression System for Cyanobacteria

Seeing in the New Light: Photoreceptor Expression System for Cyanobacteria

Cyanobacteria, the green microbial factories and photosynthetic microorganisms, have shown significant promise in addressing critical global issues such as air pollution and fuel security. These organisms can produce alternative and cleaner biofuels (e.g., bioethanol and hydrogen) and biodegradable plastics (e.g., polyhydroxy-butyrate) with minimal inputs, relying primarily on sunlight, atmospheric carbon dioxide, and basic nutrients. Such capabilities offer a timely and sustainable solution to environmental challenges. However, despite their potential, the commercial application of these biochemicals has been limited by low production yields and technological challenges. The stability and yield of production depend on the balanced and sufficient synthesis of enzymes that direct metabolic flux toward desired compounds; without this balance, excess production of one compound could strain cellular resources and reduce overall efficiency. To overcome these limitations, developing technologies that enable customizable, tunable control over enzyme production within cyanobacteria has become essential. This research aimed to create a cyanobacterial expression tool responsive to red light, using a phytochrome photoreceptor to enable precise, light-inducible gene expression. This tool would facilitate highly adjustable control of cyanobacterial gene expression through two wavelengths of red light, presenting a promising approach for optimizing enzyme levels. The project began by constructing expression plasmids and applying them to the cyanobacterium Synechocystis sp. PCC 6803. The light responses of the resulting expression strains were then tested in illumination experiments, where the increased expression of a reporter protein was measured through fluorescence spectroscopy. Although still in progress, this project aims to pave the way for more efficient and targeted protein expression in cyanobacteria, ultimately breaking production barriers and advancing cyanobacterial contributions to sustainable industrial solutions.

Data: CORDIS, © European Union